iStock
iStock

We Thought There Was One Giraffe Species—But There Are Four

iStock
iStock

For more than 250 years, there has been one universally accepted species of giraffe: Giraffa camelopardalis. But according to a study of the spotted giant’s DNA published today, September 8, in the journal Current Biology, that one species should actually be several.

This is exciting news, partly because it settles a debate about giraffe identity that’s been taking place for centuries. While Giraffa camelopardalis has enjoyed its seat at the top of the hierarchy since Carl Linnaeus officially described the animal back in 1758, there has been a lot of back and forth about just how many subspecies of giraffe truly exist. Some scientists believe there are 11 subspecies while most others argue there are just nine.

But it turns out they’re all wrong, according to the new study, which says there are actually four species of giraffe and five subspecies.

Axel Janke, a geneticist at Senckenberg Museum and Goethe University in Germany, said he and his coauthors were completely surprised by the findings.

“There is not much known about giraffes,” Janke tells mental_floss. In fact, the world’s tallest animals get far less scientific and conservation attention than other megafauna like lions and elephants.

To remedy this lack of knowledge, study lead author and Giraffe Conservation Fund co-founder Julian Fennessy spent six years sampling 190 giraffes from all over Central and Southern Africa. Thanks to special darts designed to snag a small tissue sample as they puncture an animal’s skin, Fennessy was able to collect noninvasive DNA samples from all nine accepted subspecies of giraffe, which Janke then analyzed against each other. The study represents the most expansive work on giraffe genetics to date.

Once the scientists started looking at the various genomes, they were surprised to find that all of their samples seemed to cluster into four distinct groups, each as different from the other as a polar bear is from a grizzly. Their analysis suggests that the giraffe family would be best described as containing four main species: the southern giraffe (Giraffa giraffa), the Masai giraffe (G. tippelskirchi), the reticulated giraffe (G. reticulata), and the northern giraffe (G. camelopardalis).

Furthermore, the study was able to eliminate some of the subspecies categories by showing that Thornicroft’s giraffe and the Masai giraffe are genetically identical, as are the Rothschild’s giraffe and the Nubian giraffe.

But this is more than some scholarly exercise in giraffe taxonomy.

“This paper is a much-needed wake-up call to save these magnificent animals,” Douglas Cavener, a Penn State geneticist who studies giraffes, tells mental_floss. (Cavener was not involved with the new study.)

Scientists estimate that there are around 90,000 giraffes left on Earth, he said. That’s a low number already—about a quarter of the number of elephants remaining, and elephants are in decline themselves. And if we can now say that there are four species of giraffes, each genetically distinct from the other and not thought to mate with each other in the wild, then the odds of any one of those species going extinct goes up quite a bit.

“With each of these four giraffe species now numbering less than 35,000, they are in peril of being lost forever by the end of this century,” Cavener says.

The good news is that a better understanding of giraffe genetics can help conservationists determine which species are in the most need of funding. For instance, now that they are recognized as their own species, northern giraffes and reticulated giraffes appear to be in particularly dire straits, with populations of just 4750 and 8700, respectively.

And there’s much work yet to be done. The scientists now want to sample every known population of giraffes in Africa to get an even better understanding of their distribution and genetics. And who knows what they’ll find.

“It’s not entirely impossible that we will find another species,” Janke says.

nextArticle.image_alt|e
iStock
Potato-Based Pet Food Could Be Linked to Heart Disease in Dogs
iStock
iStock

If you have a pup at home, you may want to check the ingredients listed on that bag of dog food in your cupboard. The U.S. Food & Drug Administration has warned that potato-based pet foods might be linked to heart disease in dogs, Time reports.

Foods containing lentils, peas, and other legume seeds are also a potential risk, the agency’s Center for Veterinary Medicine announced.

“We are concerned about reports of canine heart disease, known as dilated cardiomyopathy (DCM), in dogs that ate certain pet foods containing peas, lentils, other legumes or potatoes as their main ingredients,” Martine Hartogensis of the veterinary center said in a statement. “These reports are highly unusual as they are occurring in breeds not typically genetically prone to the disease.”

Recent cases of heart disease have been reported in various breeds—including golden and Labrador retrievers, miniature schnauzers, a whippet, a shih tzu, and a bulldog—and it was determined that all of the dogs had eaten food containing potatoes, peas, or lentils.

While heart disease is common in large dogs like Great Danes and Saint Bernards, it’s less common in small and medium-sized breeds (with the exception of cocker spaniels). If caught early enough, a dog’s heart function may improve with veterinary treatment and dietary changes, the FDA notes. While the department is still investigating the potential link, it’s best to err on the side of caution and avoid foods containing these ingredients until further notice.

As shown by the recent romaine lettuce scare linked to E. coli, the FDA is unable to request a food recall unless a specific manufacturer or supplier can be identified as the source of contamination. Instead, public notices are generally issued to warn consumers about a certain food while the agency continues its probe.

[h/t Time]

nextArticle.image_alt|e
iStock
10 Science-Backed Tips for Getting a Cat to Like You
iStock
iStock

Like so many other humans, you might find cats to be mysterious creatures. But believe it or not, it’s not that hard to make friends with a feline, if you know what to do. Here are some tips on how to effectively buddy up with a kitty, drawn from scientific studies and my own experience as a researcher and cat behavioral consultant.

1. LET THE CAT CALL THE SHOTS.

When we see cats, we really want to pet them—but according to two Swiss studies, the best approach is to let kitty make the first move.

Research done in 51 Swiss homes with cats has shown that when humans sit back and wait—and focus on something else, like a good book—a cat is more likely to approach, and less likely to withdraw when people respond. (This preference explains why so many kitties are attracted to people with allergies—because allergic people are usually trying to not pet them.) Another study found that interactions last longer and are more positive when the kitty both initiates the activity and decides when it ends. Play a little hard to get, and you might find that they can’t get enough of you.

2. APPROACH A CAT THE WAY THEY GREET EACH OTHER (SORT OF).

person extending finger to cat's nose
iStock

Felines who are friendly with each other greet each other nose to nose. You can mimic that behavior by offering a non-threatening finger tip at their nose level, a few inches away. Don’t hover, just bend down and gently extend your hand. Many cats will walk up and sniff your finger, and may even rub into it. Now that's a successful greeting.

3. PET CATS WHERE THEY LIKE IT MOST …

They're very sensitive to touch, and generally, they tend to like being petted in some places more than others. A small 2002 study demonstrated that cats showed more positive responses—like purring, blinking, and kneading their paws—to petting on the forehead area and the cheeks. They were more likely to react negatively—by hissing, swatting, or swishing their tails—when petted in the tail area. A more recent study validated these findings with a larger sample size—and many owners can testify to these preferences.

Of course, every animal is an individual, but these studies give us a good starting point, especially if you're meeting a cat for the first time.

4. … AND IF YOU GET NEGATIVE FEEDBACK, GIVE THE CAT SOME SPACE.

There are plenty of signs that a cat doesn't like your actions. These can range from the overt—such as hissing and biting—to the more subtle: flattening their ears, looking at your hand, or twitching their tails. When you get one of those signals, it’s time to back off.

Many of the owners I work with to correct behavioral issues don't retreat when they should, partially because they enjoy the experience of petting their cat so much that they fail to recognize that kitty isn’t enjoying it too. You can’t force a feline to like being handled (this is especially true of feral cats), but when they learn that you’ll respect their terms, the more likely they will be to trust you—and come back for more attention when they're ready.

5. DON’T OVERFEED YOUR CAT.

Many think that food equals love, and that withholding food might make your kitty hate you, but a recent study of obese felines from Cornell University showed the opposite is true—at least for a period of time. About a month after 58 overweight kitties were placed on a diet, three-quarters of their owners reported that their dieting felines were more affectionate, purred more often, and were more likely to sit in their owner's lap. This adorable behavior came with some not-so-cute side effects—the cats also begged and meowed more—but by week eight, both the good and bad behavior had abated for about half the animals.

Regardless of whether a diet makes your pet cuddlier, keeping your pet on the slender side is a great way to help them stay healthy and ward off problems like diabetes, joint pain, and uncleanliness. (Overweight animals have difficulty grooming themselves—and do you really want them sitting on your lap if they can’t keep their butt clean?)

6. PLAY WITH THEM—A LOT.

woman, cat, and feather toy
iStock

Most of the behavior problems that I've witnessed stem from boredom and a lack of routine playtime. No one thinks twice about walking their dog every day, but many people fail to recognize that felines are stealth predators who need a regular outlet for that energy. A recent study suggested that cats prefer human interaction over food, but a closer look at the data demonstrated that what really attracted them to humans was the presence of an interactive toy. One of their top choices is a wand-style toy with feathers, strings, or other prey-like attachments that evoke predatory behavior. Daily interactive play is a great way to bond with them when they’re not in the mood to cuddle—and to keep them fit. Try the Go-Cat Da Bird or any of Neko Flies interchangeable cat toys.  

7. KEEP YOUR CAT INDOORS.

A study conducted in Italy showed that felines who stayed mostly indoors (they had one hour of supervised access to a small garden each day) were more “in sync” with their owners than felines who were allowed free access to the outdoors. The indoor kitties were more active during the day, when their owners were likely to be active, and less active at night, when humans like to sleep. (Many people believe cats are nocturnal, but they are naturally crepuscular—active at dawn and dusk.)

8. SOCIALIZE CATS WHEN THEY'RE YOUNG.

Multiple studies have shown that just a few minutes a day of positive handling by humans helps kittens grow up to be friendlier and more trusting of humans. The ideal age to socialize kittens is when they're between 2 and 9 weeks old. One 2008 study found that shelter kittens that had been given a lot of "enhanced socialization"—additional attention, affection, and play—were, a year later, more affectionate with their owners and less fearful than other kittens adopted from the same shelters.

You can help socialize kittens by volunteering as a foster caretaker. Fostering ensures they get plenty of interaction with people, which will help them will be comfortable around potential adopters. You'll also be doing your local shelter a huge favor by alleviating overcrowding.

9. TAKE THE CAT'S PERSONALITY—AND YOUR OWN—INTO CONSIDERATION WHEN ADOPTING.

If you want to adopt an older animal, take some time at the shelter to get to know them first, since adopters of adult cats report that personality played a big role in their decision to take an animal home permanently and had an impact on their satisfaction with their new companion. Better yet, foster one first. Shelters can be stressful, so you'll get a better sense of what an animal is really like when they're in your home. Not all cats are socialized well when they're young, so a cat may have their own unique rules about what kinds of interactions they're okay with.

It's also key to remember that a cat's appearance isn't indicative of their personality—and it's not just black cats who get a bad rap. In 2012, I published a study with 189 participants that showed that people were likely to assign personality traits to felines based solely on their fur color. Among other things, they tended to think orange cats would be the nicest and white cats the most aloof. (Needless to say, these are inaccurate assumptions.) And it's not just the kitty's personality that matters—yours is important too. Another study I conducted in 2014 of nearly 1100 pet owners suggested that self-identified “cat people” tend to be more introverted and anxious when compared to dog people. (We’re also more prone to being open-minded and creative, so it’s not all bad.) If you’re outgoing and active, a more playful feline could be for you. If you prefer nights spent snuggling on the couch, a mellow, shy-but-sweet lovebug could be your perfect pet.

10. BE A KEEN OBSERVER OF THEIR BEHAVIOR.

Overall, use your common sense. Be a diligent and objective observer of how they respond to your actions. Feline body language can be subtle—something as small as an eye-blink can indicate contentment, while ear twitches might signal irritation—but as you learn their cues, you'll find yourself much more in tune with how they're feeling. And if you adjust your behaviors accordingly, you'll find soon enough that you've earned a cat's trust.

Mikel Delgado received her Ph.D. at UC-Berkeley in psychology studying animal behavior and human-pet relationships. She's a researcher at the UC Davis School of Veterinary Medicine and co-founder of the cat behavior consulting company Feline Minds.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios